The present invention relates to an anti-AIDS virus agent (anti-HIV agent) containing as an active agent 2-amino-6-chloropurine-9-.beta.-D-2',3'-dideoxyribofuranoside and a therapeutic or preventive drug for AIDS containing said active agent.
Various anti-AIDS agents (anti-HIV agents) currently exist. Such agents include dideoxynucleosides such as azidothymidine (AZT), dideoxyadenosine (DDA) and dideoxyinosine (DDI). Dextran sulfate, soluble CD4, phosphonoformate, ribavirin, suramine, etc. are also known to be anti-AIDS virus agents (anti-HIV agents).
Since the anti-HIV property of AZT, DDA, DDI, etc., was recognized, new dideoxynucleosides modified with various substituents have been synthesized and proposed as new anti-HIV agents. Among these compounds, for example, are compounds having a halogen atom in the molecule, 6-chloropurine-9-.beta.-D-2',3'-dideoxyribofuranoside and 6-iodopurine-9-.beta.-2',3'-dideoxyribofuranoside (Japanese Unexamined Patent Publication No. Sho 63-267796). Moreover, 2-fluoro-2',3'-dideoxyadenosine and 2-bromo-2',3'-dideoxyadenosine are known (J. Biol. Chem., 263, 5870 (1988). Furthermore, 2-chloro-2',3'-dideoxyadenosine (J. Biol. Chem., 263, 5870 (1988); J. Med. Chem., 32, 1135 (1989) and 2-chloro-2',3'-didehydro-2',3'-dideoxyadenosine (J. Med. Chem., 32, 1135 (1989) are also known.
Similar compounds such as 9-(2-fluoro-2,3-dideoxy-.beta.-D-threopentofuranosyl)-adenine etc. are also known (J. Med. Chem., 30, 2131 (1987).
Among the above compounds, however, the only one currently approved as a therapeutic drug for AIDS is AZT.
Most of the publicly-known anti-AIDS virus agents (anti-HIV agents) aforementioned have drawbacks including the points of the activity against AIDS virus (HIV), toxicity to cells, absorptivity into living bodies, etc. Moreover, with AZT being the only drug approved, side-effects such as myelotoxicty, etc. are known. Thus, additional anti-AIDS virus agents (anti-HIV agents) are currently a goal of the industry.
The purpose of the invention is to provide an anti-AIDS virus agent (anti-HIV agent) in order to solve the above problems.
The invention is based on the findings that 2-amino-6-chloropurine-9-.beta.-D-2',3'-dideoxyribofuranoside has a high anti-AIDS virus activity and yet has a high absorptivity into cells.